Fluid operated pump



Dec. 25, 1962 c. o. GLASGOW FLUID OPERATED PUMP INVENTOR ATTORNEYSClarence 0. Glasgow Dec. 25, 1962 c. o.-GLAsGow 3,070,023

FLUID OPERATED PUMP Filed Sept. 28, 1959 4 Sheets-Sheet 2 43' 23 INVENTOR Clarence 0. G/asgow ATTORNEYS Dec. 25, 1962 c. o. GLASGOW3,070,023

FLUID OPERATED PUMP Filed Sept. 28. 1959 4 Sheets-Sheet 3 Figi /55 mf I./INVENTOR f C/arence 0. vG/asgow ATTORNEYS Dec- 25, 1962 C. o. GLAsGow3,070,02 3l FLUID OPERTED PUMP Filed Sept. 28, 1959 4 Sheets-Sheet 4Fig. 8

INVENTOR Clarence 0. G/asgow ATTORNEYS rares 'arent 3,070,023 PatentedDec. 25, 1962 Fie 3,070,023 FLUID QPERA'EED PUMP Clarence 0. Glasgow,Tuisa, kla., assigner to National Tank Company, Tulsa, Uleila., acorporation of Nevada Filed Sept. 28, 1959, Ser. No. 842,831 1l Claims.(Cl. 10S- 51) This invention relates to new and useful improvements influid operated pumps.

There are many instances in which it is necessary or desirable to pump afluid, usually a liquid, into a vessel, conductor, or other enclosureunder relatively high pressure utilizing a low or intermediatelypressured iluid as a source of motive power. It is often necessary onlyto pump relatively small quantities of liuid or liquid into the highpressure system, usually under adjustable orV of economy as well asreasons of continuity of operation` and ability to function properly inremote locations where electric power and similar conventional sourcesof motive power may not be available.

A specific example of a fluid operated pump of the nature set forth isto be found in the oil elds in which large flowing volumes of naturalgas may require dehydration or other treatment prior to entry into a gastransmission pipe line. In particular, it is conventional to pass largevolumes of natural gas through dehydration towers or dehydrationequipment in which the gas is brought into intimate contact with aconcentrated glycol solution, such as 96 percent or 98 percentdiethylene or triethylene glycol, in order to remove from the naturalgas virtually all of the moisture present so that the gas maysubsequently be introduced into and flowed through a gas transmissionpipe line Without the danger of gas hydrates occurring. In such aninstallation, it may be necessary to pump the glycol solution into acontactor tower operating at pressures of from 1500 to 2G00 pounds persquare inch or more, and yet, it is desirable to employ as a source ofmotive power natural gas or other uid under moderate pressures up to themagnitude of 100 pounds per square inch. ln connection with thisparticular example, it has been found in the past that existing pumpstructures present diicult leakage problems, especially in the glycolcircuit, that they are not always positive in action so as to providecontinuity of the pumping operation, and that the flow rates are notalways too readily established and maintained at a pre-selected level.In a glycol dehydration system of this type, it is the usual practice topump to the concentrated glycol into the contactor tower, to remove thedilute or spent glycol solution therefrom and subject it to a heatingstep in which excess moisture is removed so that the reconcentratedglycol may again be returned to the gas contacting tower. In thismanner, the glycol flows in a continuous circuit, absorbing moisturefrom the natural gas stream and being relieved of such moisture in theheating or regenerating equipment.

Many other similar uses of Huid operated pumps are to be encountered,but for the purposes of brevity and clarity, the invention will bedescribed largely with respect to utilization of the fluid operated pumpin connection with the glycol system or circuit of a natural gas it is aprincipal object of this invention to provide an improved fiuid operatedpump adapted to utilize fluid under l relatively low pressure as asource of motive power and to pump a second fluid into a high pressuresystem in a completely positive fashion with continuous and trouble freeoperation assured, and with elimination to a large degree of theproblems of leakage, irregular or shifting pumping rates, as well as themaintaining of reliable and certain pumping operations in remotelocations with very infrequent inspection and maintenance.

A particular object of the invention is to provide an improved fluidoperated pump of the reciprocating type in which a quick and positivesnap action is obtained in the valve 0r valves controlling the ow ofmotivating fluid under pressure so as to make certain the positive,quick, and exact reversal of movement of the driving piston at each endof its stroke.

An additional object of the invention is to provide an improvedstructure of the character described in which the same piston may beemployed as both a driving piston and a driven piston, and which may besingle or double acting in operation.

A further object of the invention is to provide an improved uid operatedpump particularly adapted for utilization in the glycolcircuit of anatural gas dehydration system, and in which provision is made forsimultaneous pumping of both the concentrated and dilute glycolsolutions, and in which dilute glycol and/or natural gas under pressuremay be employed as the motivating fluidl under pressure.

Yet an additional object of the invention is to provide the newcombination of a fluid operated pump employing unique snap action Valvesfor the purpose of switching the motivating fluid under pressure asrequired for reciprocation of the driving piston of the pump withassurance of positive and very quick reversal of flow of the motivatingfluid between different sides of the actuating piston.

Other and more particular objects of the invention will appear from areading of the following description and by reference to the claimsappended hereto. i

A construction designed to carry out the inventionwill be hereinafterdescribed, together with other features` of the invention.

The invention will be more readily understood from a reading of thefollowing specification and by reference f to the accompanying drawings,wherein examples-of the invention are shown, and wherein: FIG. 1 is alongitudinal, horizontal, sectional view of a uid operated pumpconstructed in accordance withthis invention, certain of the partshaving been rotated; in the view in order to illustrate the structuremore clearly,I

FIG. 2 is a fragmentary view of one of the pump ends of the form of theinvention shown in FIG. 1, the view being taken at right angles to FIG.l upon the line 2-2 there-` FIG. 3 is a longitudinal, vertical,sectional view of a modification of the pump of FIG. l, certain of theoperating connections being shown diagrammatically,

FIG. 4 is a schematic view of a further modification of the invention,

FIG. S is a schematic illustration of an additional modication of theinvention,

FIG. 6 is a schematic View of a still further modication of theinvention,

FIG. 7 is a schematic view of a single ended variation of the modicationof FIG. 6, and

I supported upon any suitable type of pedestal or base for attachment toand mounting upon a foundation or other suitable supporting member (notshown). The cylinder is formed with annular, outwardly extending llanges11 and 12 at its left and right hand ends, respectively, an annulargroove being cut in the inner periphery of the face of each of theflanges 11 and 12 for receiving suitable sealing O rings 13. A head 14projects a short distance into the left hand end of the cylinder 10 andis formed with a marginal flange 15 forming a shoulder enclosing the Oring 13, the flange 15 being connected to the ilange 11 by suitablebolts 16. The inner face of the head 14 is chamfered and cut away toform an annulus 17 adjoining the inner Wall of the cylinder lil and toprovide an annular clearance space for purposes to be describedhereinafter. The head 14 carries a central, outwardly extending neck 1?formed integrally with the head and having an axial bore 19 opening intothe interior of the cylinder 19. Intermediate the end portions of theneck 18, the bore 19 is enlarged to form a circumferential chamber 20'of greater diameter than the bore 19 and terminating short of the innerand outer ends of the neck 18. A tubular pump chamber 21 having a closedouter end 22 is provided with an intermediate, outwardly extendingflange 2 3 which abuts the outer end of the neck 18 and is securedthereto by suitable bolts 24. The portion 25 of the pump enclosure 21inwardly of the flange 23 is reduced in outside diameter and receivedwithin the outer portion of the bore 19, the inner end of the reducedportion 25 terminating within the chamber 20 adjacent to the inner endthereof. A packing sleeve 26 is positioned in the inner portion of thebore 19 and sealed with respect thereto by a pair of spaced gasketmembers 27, the sleeve being provided near its outer end with anexternal flange 28 disposed within the chamber 2d and abutting the innerend of the reduced portion 25. Suitable screws or bolts, or otherconnecting elements 29 secure the outer end of the sleeve 26 to theinner end of the reduced portion 25.

On the right end of the cylinder 10 upon the flange 12, a cylinder headand pump assembly is mounted. The right hand assembly is substantially amirror image of the left hand assembly described above, and the samenumerals have been applied to similar elements with the numerals beingprimed.

Bleeder or tell-tale passages 39 and 39' extend from between the gaskets27 and the gaskets 27 to the peripheries of the flanges 15 and 15',respectively, for discharging any lluid which may accumulate between thegaskets and conducting such fluid exteriorly to a suitable container orother enclosure in which the lluid may be detected and the presence ofleakage between the respective sleeves and heads ascertained.

A motor piston 30 is disposed within the cylinder 10 between the heads14 and 14 and arranged for longitudinal movement Within the cylinder,the piston being provided with a marginal piston ring 31, preferablyformed of some suitable elastomer and engaging the inner wall of thecylinder 10 in snug sliding relationship. The piston 30 is formed withopposed, substantially planar outer faces so that when the piston isclosely adjacent either of the heads 14 or 14', the annuli 1.7 and 17will remain open. A plunger rod 32 is secured to the center of thepiston 30 extending axially thereof and being formed with a left handpump plunger 33 extending from the piston 30 through the sleeve 26 andinto the pump enclosure 21, the opposite end of the rod 32 forming aright hand pump plunger 34 which extends from the piston 30 through thesleeve 26' and into the pump enclosure 21. Suitable sealing gaskets 35and 35 are provided between the sleeve 26 and the left hand pumpplunger'33 and between the sleeve 26 and the right hand pump plunger 34.As may be observed in FIG. l, the plungers 33 and 34 are of sufficientlength that the outer extremities thereof are not completely withdrawnfrom the pump enclosures 21 and 21 when the piston 35 is in either itsextreme right hand or extreme left hand position.

Referring now to FIG. 2 which is a sectional view of the right hand endof FIG. l but taken at right angles thereto, it will be seen that thereduced portion 25' of the pumping enclosure 21' is provided with a pairof diametrically opposed ports 36 opening from the interior of thepumping enclosure around the pump plunger 34 to the circumferentialchamber or enclosure 26. ment With one of the ports 36 the neck 1S isformed with an integral, laterally extending inlet collar 37 having albushing 38 screw threaded into its outer end and receiv-j ing an inletconductor 39". An inlet check valve 49 is carried upon the inner end ofthe bushing 38 and arranged to allow lluid to enter into the enclosure20 from the conductor 39 but to prevent reverse flow of fluid from theenclosure 26 to the conductor 39. Similarly, the opposite port 36 is inregistry with an outlet collar 41 formed integrally of the neck 18 andcarrying a bushing 42 in its outer end, the bushing being connected toan outlet conductor 43. An outlet check valve 4d' is carried by theinner end of the bushing 42 and arranged to permit tluid to llowoutwardly from the enclosure 25) to the conductor 43 but to preventreverse ilow of the fluid. Although it is not illustrated in thedrawings, the opposite head 14 and neck 18 are provided with identicalinlet and outlet collars and conductors carrying identical inlet andoutlet check valves.

With this arrangement, as the piston 30 is reciprocated Within thecylinder lll, lirst the pump plunger 33 is caused to move to the left,Ias viewed in FIG. l, into the pumping enclosure 21 so as to 'forcefluid therefrom through the outlet conductor thereof whilesimultaneously the pump plunger 3dis withdrawn from the pump enclosure21' to draw tluid thereinto from the conductor 39. As the pistonreverses its movement and returns to the position shown in FIG. l, theplunger 33 is withdrawn from the enclosure 21, drawing additionalquantities of iluid thereinto, while the plunger 34 is moved into theenclosure 21" forcing fluid therefrom outwardly under pressure throughvthe outlet conductor 43. Of course, two different lluid'st may be pumpedby the two pumping enclosures, but pref"r erably the inlet conductors ofthe pumping enclosuresi 21 and 21 are connected in manifold to drawtluid from; a common source, and the outlet conductors of the enclosuresmay also be connected in manifold to direct the' fluid under pressure toa common point. In this manner; the structure becomes a double actingpump in that iluidI i's pumped under pressure through the outletconductorsl upon both strokes of the piston 311. It is also be be notedthat the diameter, and hence, the exposed area of the pis-- ton 30 isquite large in comparison with the diameters. and exposed areas of theplungers 33 and 34, and accord-- ingly, a motive fluid under a pressureof possibly pounds per square inch is entirely capable of pumping -iluidfrom the enclosures 7,1 and 21 at a pressure of ythe ordrr of magnitudeof several thousand pounds per squarey mc For supplying motive luidunder pressure alternately to opposite sides of the piston 3), aconventional four-way' valve 45 is mounted upon one outer wall of thecylinder 10, the valve being of the springless variety adapted to haveits switching plunger actuated through diaphragms, pistons, or othersuitable devices. Such valves are well known in this art and need not bedescribed at length except to point out that the valve has provision forconnection to a pressure fluid inlet conductor 46, a pair of outletconductors 47 and 48 and vent ports 49 and 56. The reciprocable plunger51 is adapted to be shifted longitudinally of the valve structure toplace the conductor 45 alternately in communication with the conductor47 while exposing the conductor 4S to the vent 5d, and upon shifting ofthe plunger 51, to place the conductor 46 in communication with theconductor 48, while shutting oil the vent 5% and exposing the conductor457 to the Vent 49. In `this manner, motivating fluid under pressure isalternately supplied to one of the conductors 47 or 45,

In align-4 while the opposite one of the conductors 47 `and 48 isexposed to a vent, the vent of the pressurized conductor being closedolf while pressure lluid is being supplied thereto. For shifting theplunger 51 longitudinally, there is provided at the left hand end or"the valve 45 a cylinder 52 communicating with an inlet conductor 53 andenclosing a piston 54 which is connected to one end of saidy plunger. Atthe right hand end of the four-way valve there is provided a cylinder 55having a conductor 56 connected thereinto and enclosing a piston 57connected to the right hand end of the plunger 51. Since no springs areincluded in the valve d5, it is apparent that supplying of fluid underpressure to the conductor 53 and venting of the conductor 56 will shiftthe plunger 51 to the right into the position shown in HG. 1, whileventing of said conductor 53 and pressurizing of said conductor willshift the plunger 51 to the left to vent the conductor and supply tluidunder pressure to the conductor iti from the conductor 46.

The conductors t7 and 48 are connected through the llanges 11 and 12with the annuli 17 and 17', the arrangement of the right hand end of thepump being shown in FIG. 2 in which the conductor 43 is connected to anelbow 5S screw-threadedly mounted in the llange 12 in communication witha port 59' leading to the annulus 17. In this manner, as pressure fluidis supplied to the conductor 48 it is also supplied to the annulus 17and serves to drive the piston 36 to the left. As pressure liuid isalternately supplied to the conductor 47, such lluid will ow to theannulus i7 and drive the piston 30 to the right. Consequently, as Vtheplunger 51 is shifted to the lett and to the right, motivating fluidunder pressure is alternately supplied to the conductors i7 and 48 toreciprocate the piston 36 within the cylinder 1t). `For switching orshifting the four-way valve i5 from its right hand position to its lefthand position and return, the heads 1d and 1li carry pilot plungerassemblies 6i) and 6d respectively, snap action, toggle-type, pilotvalves 61 and 61 being mounted respectively upon the assemblies 60 and61,. The pilot plunger assemblies 60 and 66 are identical in structure,the assembly 6i) being shown in detail in FIG. 1 and including anelongate housing 62 provided at one end with a screw-threaded nipple 63secured in a screw-threaded `bore 64 opening through the head 1d intothe annulus 17. A pilot plunger 65 is reciprocable within the nipple 63and extends through a suitable packing gland 66 into the interior of thehousing 62. A stop member 67 is adgustably secured upon the plunger 65within the housing 62 so as to abut the gland 66 and limit inwardmovement of the plunger 65, and a pair of inner Iand outer actuatingrings 63 and 69 are adjustably positioned upon plunger 65 within thehousing 62. The outer end or the housing is closed by a screwthreadedplug 76, a compression spring 71 being conlined between the plug 7d andthe outer ring 69 for urging the plunger 65 constantly inward.

The snap-action pilot valves 61 and 61 are also substantially identicalin structure -and are desirably of the type disclosed and described inUnited States Letters Patent No. 2,860,660. The pilot valve 61 hasconnected thereto a pilot gas inlet conductor 72 and a vent conductor73, the valve being adapted to place 4the conductors 72 and 73alternately in communication with the conductor 53 which is connected tothe cylinder 52 of the fourway valve 45. The actuating pin or arm 74 ofthe valve 61 extends into the pilot plunger housing 62 into the spacebetween the rings 63 and 69 and is adapted to be swung to the right andto the left, as viewed in FIG. 1, by the rings 63 and 69 as the plunger65 is reciprocated. rl`he pilot valve 61 is similarly arranged having apilot gas inlet or supply conductor 72', a vent conductor 73', and beingadapted to place the conductors 72 and 73 alternately in communicationwith the conductor 56 which is connected to the cylinder 55 of thefour-way valve 45.

The plungers 65 and 65 are of such length as to project in their inwardposition into the cylinder 10 past the annuli 17 and 17' so as to be inposition for engagement by the piston 30 at each end of the stroke ofthe piston. Thus, .in the position of the pump shown in FlG. l,motivating fluid under pressure is being passed from the conductor 46through the valve 45 to the conductor 47 and into the left hand side ofthe cylinder 10 to drive the piston 30 to the right hand end of itsstroke and pump fluid under pressure from the enclosure 21' outwardlythrough the outlet conductor 43. As the pis ton 351 reaches lthe righthand end of its stroke, `it engages the plunger 65 to shift the righthand plunger assembly 60 and the valve 61', shutting off the venting ofthe conductor 56 to the vent 73 and exposing the conductor 725 to theconductor 56 to direct pilot fluid under pres-v sure into the cylinder55 to force the piston 57 and the plunger 51 to the left. As will appearmore fully hereinafter, the pilot valve 61 is lin a venting positionsothat the conductor 53 and cylinder 52 are vented to the atmosphere,and hence, there is no resistance offered to left hand movement of theplunger '51. Movement of the plunger in this direction will result inventing of the conductor 47 through the vent 49, thus venting the lefthand portion of the interior of the cylinder 10, and the closing of thevent 50 while placing the motivating fluid inlet conductor 46 incommunication with conductor 48. Fluid under pressure -is thus admittedto the righ-t hand end of the cylinder 10 and allowed to act upon theright hand face of the piston 3A0, commencing 'he left hand movement ofthe piston and the pumping of iluid under pressure from the left handenclosure 21 while drawing additional supplies `of fluid into ythe righthand enclosure 21. As the piston moves away from the right hand pilotplunger assembly 60', the plunger 65 will move into the interior of thecylinder 10 under the inlluence of its spring, thus again shifting thepilot valve 61 and exposing the conductor 56 and the cylinder 55 to thevent 73. Since the four-way valve 45 -is of the yspringless variety,however, no movement of the plunger 51 will result. The left handmovement of the piston 36 continues until it encounters the plunger 65moving the plunger outwardly to momentarily shift the valve 61, closingolf vent 73 and exposing the pilot fluid inlet conduotor 72 to thecylinder 52 to drive the piston 54 and the plunger 51 to the right,venting the conductor 48 and pressurizing the conductor 47. In thismanner, the snap-action pilot valves 61 and 61 function to providemomentary supplying of fluid under pressure alternately to the cylinders52 and 55 to reciprocate the plunger 5'1 and alternate the supply ofmotivating Huid under pressure to the left and right hand sides of thepiston 36, while reciprocating the piston and alternately pumping thelluid under pressure from the enclosures 21 and 21.

It is to be noted that the utilization of the snap-action pilot valves61 and 61 along with the provision of means whereby the valves vareactuated only on a momentary basis .and are then returned to a ventingposition, results in very quick and positive laction of the switching orfourway valve 45, and the very positive and delinite reciprocation ofthe piston 36 within the cylinder 10 regardless of th-e slowness withwhich the piston is moving and the slowness or the low rate at whichfluid is being pumped from the enclosures 21 and 21. Since the spacingbetween the rings 63 and `69 is considerably greater than the lare ofmovement of the arm 74, yand since snapaction ltoggle-type, pilot valvesare employed, the pilot valves will operate almost instantaneouslyregardless of the fact that the ring 68, in accordance with the movement`of the plunger 65 and the piston 3Q, may be moving at a rate so slow as`to be almost imperceptible. An ultimate point will be reached at whichthe arm 74 will snap past dead center, and the valve 61 wil-l movealmost instantaneously from la venting position to a pressurizingposition, positively shif-ting the plunger 51 and ensuring certainreversal in movement of the piston 3i). Similarly, as the piston 30'retreats from the plunger 65, a point will be reached at which the ring69 will have moved the arm 74 suticiently to cause the arm to snap thepilot valve 61, again, almost instantaneously, to a venting position soas to prepare the valve 61 for proper venting of the cylinder 52 uponsubsequent reversa-l in movement of the piston 36. In this way, a newcombination has been provided in utilizing positively actuated trippingmeans .for snap-action pilot valves, the interconnection between theactuating means and the valves being such as not to impair the almostinstantaneous action of the valves so that positive and reliablecontinuous operation of the pumping mechanism is ensured regardless ofthe slowness or the rapidity with which huid is being pumped by themechanism. All gradual opening and closing or" valves is eliminatedthrough the combining of the main pumping structure, the snap-action,toggletype pilot valves, land the springless four-way valve e5.

Of course, any suitable type of needle or control valve may beincorporated into the conductor e6 or the conductors 47 or 48 forcontrolling the supply of motivating lluid under pressure .and thuscontrolling the rate at which the piston 30 moves so as Ito controlindirectly the rate at which uid is pumped from the enclosures 2J; and213i'.

In conjunction with a glycol type natural gas dehydratling system, theconductors 72 and 72 are desirably supplied with natural gas through apressure reducing valve at a pressure of to 30 pounds per square inch,the conlductor 46 supplied with natural gas under a pressure of itheorder of magnitude of 1G() pounds per square inch, .and the inletconductors to the enclosures 2l and 2l connected to the supply ofconcentrated glycol solution. The outlet conductors from the enclosures21 and 2li will, of course, lead to ,the contacting or dehydration towerfor supplying of concentrated glycol solution thereto for dehydration ofthe natural gas stream. rl`he pilot gas land motivating gas underpressure may desirably be tapped from any suitable point in thedehydration system as, for instance, from the down stream side of thedehydration `tower from which clean and dry natural gas may be withdrawnthrough suitable pressure reducing valves or pressure regulators forsupply at the proper or desired pressure.

In the first form of the invention, the positive and certain snap-actionof the pilot valves was obtained by mechanical abutment and directmechanical movement between the piston and the plunger rods 65 and 65.

In the remaining kforms of the invention, however, the

direct and certain mechanical movement of the snapaction pilot valves isobtained by direct actuation of the pilot valves yfrom the piston rod orplunger itself. Thus, in FIG. 3, there is shown a single actingmodication of the first form of the invention, this form including abase or support 75 having formed thereon an integral cylinder head 76having a circular, laterally extending rib 77 surrounding a circularrecess or annulus '7S enclosing a central hub 79. A cylinder 80 ismounted in sealing engagement with the periphery of the rib 77 andreceives upon its opposite end a second cylinder head Si also arrangedin sealing engagement with the right hand end of the cylinder 80, bothcylinder heads being suita-bly secured to each other or to the cylinderSti for pressure tight enclosure. The head 31 is provided with anannular rib or ange S2 extending into the cylinder 8d in snug sealingengagement therewith and surrounding a concave, arcuate annulus S3enclosing a central hub 34. An axial opening extends through the hub Seand the head :'31 and receives an elongate pilot valve actuating rod'for reciprocal movement. A packing d'7 is provided in the outer face ofthe head 81 encircling the rod 86, and is urged into packing position bya screw threaded packing gland 8S having a screw threaded nipple S9extending therefrom and supporting an actuating ring hous- ,ovens inggli. The rod S6 extends through the nipple 89 into the housing 9@ andcarries upon its extremity a pair of spaced, adjustable, inner and outeractuating rings 91 and 92, respectively, for engaging the actuating arm93 of a pilot valve 94 similar to the valves nl and 6l'.

A piston is positioned for reciprocation within the cylinder ed, thepiston being provi-ded with a marginal sealing ring 96, formed of somesuitable elastomer or other material and having a central, headedbushing 97 slidably engaging the rod d6. The bushing 97 has its headpositioned upon the right hand face of the piston 95, as viewed in FIG.3, and its screw-threaded shank 93 extending through the piston `andinto the screwthreaded hollow interior of an elongate pump plunger 9?.The plunger 99 is reciprocable within a pump barrel im draped to thehead Ydby a suitable plate 101 and bo 2, the inner end of the barrel 166carrying suitable scaling rings or gaskets and being received in acylindrical recess formed in the outer face of the head 76 and extendinginto the central hub 79. The hub carries a suitable packing or packinggland 103 adjoining the inner end or" the barrel Miti and encircling theplunger 99 so as to prevent leakage therebetween. In addition, asecondary packing element 104 is recessed in the barrel lllii outwardlyof the packing 93, and a seepage or telltale passage 65 extends frombetween the packings 103 and Ittl through the hub '76 to an outletconductor 106 directed to a suitable container for detection of leakagebetween the plunger 9? and the `barrel Miti. Suitable inlet and outletconductors and check valves 1&7 and 10S', respectively, are connectedinto the outer end of the barrel llt'ti.

The hollow plunger g@ is `formed with a cylindrical bore la7 extendingfrom the threaded shank 98 of the bushing 97 to a point spaced from theouter end of the plunger. The rod S6 extends through the bushing 97 intothe bore 107 and is provided on its outer end with a cylindrical headFSS having a relatively loose t within the bore 07 so as to provideample lateral clearance for unrestricted reciprocation of the head 108within the bore M7. As will be seen more fully, hereinafter, the bore M7is of a length slightly less than the stroke of the piston for thepurpose of actuating the pilot valve 94.

A motive gas supply conductor 109 has a branch conductor lll@ connectedthrough a reducing valve 111 to the inlet ttin g M2 of the pilot valve94, the latter valve also having a vent conductor M3 and an outletconductor tile leading to the diaphragm housing 115 of a motor operated,four-way valve 116. The supply conductor b9 extends through a control orregulating valve 117 to one inlet of the four-way valve 116, .the valve116 being provided with a vent or outlet HS, a rst supply conductor il@leading to an inlet iitting 12u extending through the head 7d intocommunication with the recess 78, and a second outlet conductor IZIleading to an inlet fitting PL2?. `connected into the annular recess 83of the head Sl.

In the operation of this second form of the invention and assuming thatthe structure is in the position shown in FIG. 3 in which the piston g5has just reached the left hand end of its stroke so that the ring 92 hastripped the arm 93 of the valve 94 to move it into the position in whichthe inlet conductor 112 is placed in communication with the outletconductor H4, gas or other suitable motive fluid under reduced pressureis supplied to the diaphragm housing 115 to shift the valve 116 into theposition shown in FIG. 3. In this position, motive fluid under pressureis supplied from the conductor 169 to `the tting 12d and into the spaceto the left of the piston 95 so as to drive the piston to the right. Tobe exact, the piston 95, in the position shown in FIG. 3, has justcommenced its right hand travel. Since the rod 36 is slidable within thebushing 97, it is immaterial whether gas or other iiuid leaks throughthe bushing into the bore M7 which is eectively sealed from the lefthand side of the piston 95 by the engagement of the inner end of theplunger 99 with the left hand side of the piston 95. Under pressure ofthe motive fluid the piston will move to the right, but the rod 86 willremain stationary due to the frictional resistance exerted by thepacking S7. The plunger 99 is thus withdrawn from the cylinder 190,drawing additional iluid into the cylinder from lthe inlet conductor1127', and this action continues until the piston 95 approaches theright hand end of its stroke, at which time the bottom of the bore 197will engage the head 19S of the rod S6 to shift the rod to the right andcause the ring 91 to engage the arm 93 and snap-actuate the pilot valve94 for switching the valve into a position in which the inlet 112 isisolated from the outlet 114 and the latter is connected to the vent113. Pressure gas is thus vented from the diaphragm housing 115, and thevalve 116 is switched to place the inlet conductor 169 in communicationwith the conductor 112 while the conductor 119 is Vented to the outlet118. The space within the cylinder S to the left of the piston 95 isthus vented to the atmosphere while pressure is supplied through thefitting 122 to the right hand side of the piston to drive the piston ina reverse direction to the left and force the plunger 99 into thecylinder 1110, pumping uid under high pressure outwardly through theoutlet conductor 16S'. This action continues until the piston 95 reachesthe left hand end of its stroke, at which time the shank 98 of thebushing 97 engages the head 108 to shift the rod `86 to the left andbring the ring 92 into engagement with the arm 93 to return the valve 94to its original position and again commence admission of uid underpressure to the space enclosed between the head 76 and the piston 95 formovement of the piston tothe right. Obviously, this action continuesalternately and indelinitely. it is to be noted that the hubs 79 and S4limit the left and right hand movement of the piston 95, and that theannular recesses 7S and 83 ensure sufficient clearance for admission ofmotivating fluid under pressure to either side of the piston 95 so thatthe apparatus may not become locked in any fashion. Again, the spacingbetween the rings 91 and 92 is sul'licient as to permit full snap-actionof the arm 93 and snap-operation of the valve 94 -for substantiallyinstantaneous reversal in the movement of the piston 95. The piston isnot directly or rigidly connected to the actuating rings which engagethe pilot switch arm 93, but at the desired times of actuation there isa direct mechanical connection or mechanical abutment between theseveral parts for positive and certain shifting `of the pilot valve.

A further modification of the invention is shown in FiG. 4, this lattermodification involving direct controlling or" the pilot valve by thepump and motor rod, and also making provision for pumping two iluids,as, for instance, in the case of a natural gas dehydration towerutilizing a glycol solution, the pumping structure makes provision forpumping concentrated glycol solution to the tower while simultaneouslypumping spent or dilute glycol solution from the tower to thereconcentration apparatus. The structure includes an enclosed cylinder123 carrying a packing gland 124 upon its upper end and supporting adiaphragm housing 125 having therein a flexible diaphragm or otherpressure responsive element 126 dividing the housing 125 into an upperchamber 127 and a lower chamber 123. A reduced diameter enclosure 129extends upwardly from the diaphragm housing and supports a pilot valve13@- similar in all respects to the pilot valves 61 and 61 hereinafterdescribed. A concentrated glycol solution, or other iiuid, inletconductor 131 extends through a check valve 132 into the upper portionof the cylinder 123, an outlet conductor 133 extending from the upperend of the cylinder 123 through a check valve 134. A branch conductor135 communicates between the inlet conductor 131 up stream of the checkvalve 133 with the chamber 128 through a needle Valve or other type ofhow control valve 136.

A three-way diaphragm or motor operated valve 137 has a tiuid inletconductor 138 connected thereto, as, for instance, a dilute glycolsolution conductor leading from the bottom of a dehydration tower, thevalve also being provided with an outlet conductor 139 and a thirdconductor 140 connected into the lower end of the cylinder 123 andadapted to be placed into communication with either the conductor 138 orthe conductor 139 through switching of the valve 137.

The pilot valve 13() has a pilot gas supply conductor 14.1 connectedthereto along with a ven-t conductor 142 and an actuating conductor 143leading to the diaphragm or other actuating mechanism of the valve 137and having a branch conductor 144 communicating with the chamber 127.Within the cylinder 123, a piston 145 is reciprocally positioned andcarries a piston rod 146 extending upwardly through the packing gland124 and through the diaphragm 126 into the enclosure 129. The rod 1416is secured to the diaphragm 126 so as to move therewith, the upperextremity of the piston rod carrying a pair of spaced actuating rings147 adapted to engage alternately the operating arm or lever 148 of thepilot `'alve 1311, said arm projecting from the pilot valve through thesidewall of the enclosure 129 and into position between the rings 147.It is to be noted thatgthe entire underside of the piston 145 is exposedto the lower end of the cylinder 123 while the area of the upper side ofthe piston exposed to the upper portion of the cylinder is reduced by anamount equal to the'cross-sectional area of the piston rod 146.

ln the operation of this form `of the invention and assuming that thepiston 145 has just commenced its upward stroke, the pilot valve beingin a venting position so as to vent the conductors 143 and 144 andremove pressure from the upper side of the diaphragm 126 whiledepressurizing the diaphragm operator of the valve 137 and placing theconductors 138 and 14@ in communication, dilute glycol solution and gaswill How under the pressure of `the dehydrator tower into the cylinder123 below the piston 145 forcing the piston upwardly an-d expellingconcentrated glycol solution, or other fluid from the space above thepiston 145 through the outlet conductor 13.3 and into the dehydratortower or other point of delivery. As stated above, the differentialareas between the upper and lower sides of the piston 145 will permitthis action to take place, the diaphragm 126 offering no resistance tomovement other than the rate at which iluid can be drawn into thechamber 128 through the conductor in accordance with the setting of thevalve 136. When the piston reaches the upper end of its stroke, thelower actuating ring 147 will contact the arm 148 to shift the valve130, placing the pilot gas supply conductor 141 in communication withconductors 143 and 144, thus applying pressure to the top of thediaphragm 126 and switching the valve 137 to place the conductor incommunication with the conductor 139. The diaphragm 126 is of asufficient area as to force the piston downwardly, delivering diluteglycol solution or other iuids from beneath the piston through theoutlet conductor 139 to the dehydration apparatus or other point ofdelivery while drawing a fresh quantity of concentrated glycol solutionor other uid into the upper part of the cylinder 123 through the inletconductor 131. The rate at which this action takes place will again bedependent upon the setting of the valve 136 since fluid must beexhausted from the chamber 1213 through the conductor 135 and into theconductor 131 so that concentrated glycol solution or other fluid, inactuality, surges in and out of the chamber 128 at a rate determined bythe setting of the valve 136 so as to control the rapidity of movementof the piston 145 on both its upward and downward strokes and thuscontrol the overall rate of pumping of both the iiuid entering throughthe conductor 131 as well as `the fluids entering through the conductor133.

aoraoae' Upon reaching the bottom of the piston stroke, the apparatusfunctions to switch the arm 143 downwardly by engagement therewith ofthe upper ring 147, again switching the pilot valve 130 to vent thechamber 127 and return the conductor 138 to communication with theconductor 140.

It is quite apparent that by reason of the larger piston area exposedand consequently the larger volume in the lower portion of the cylinder123 as compared with the upper portion thereof, the unit cannot continueto operate solely by the flow of glycol solution or other liquid butmust also utilize the flow of some gas or other tluid through theconductor 13S into the space below the piston 145. The unit will thusfunction, in the case of the natural gas dehydration tower utilizingglycol solution, to maintain the drainage chamber or enclosure of thedehydrator tower substantially free of glycol solution, or in any eventto remove the glycol solution as -fast as it accumulates therein. Thus,the unit is functioning under the motive force of the pressure existentwithin the glycol tower or source of tluid under pressure whichconstantly drives the glycol or other -iiuid from the tower and inreality utilizes a portion of the gas as well as the pressure of the gaspresent within the tower yfor motivation.

A modification of the above arrangement is shown in FIG. of the drawingsin which the pressure under which the dilute glycol solution or otheruid iiows to the assembly' is not necessarily critical, there beingprovided an outside source of motive power for driving the pumping unit.Although `appearing slightly diiierent from a schematic view point, inessence the structure is the same as that shown in FIG. 4, the samenumerals being utilized to identify substantially the same elements ortheir equivalents, with the exception that the conductor 144, instead ofbeing connected into the chamber 127 of the diaphragm housing 125 isconnected to the diaphragm housing 149 of a four-way valve 151i. Aconductor 151 leads to the valve 156 for supplying motivating uid underpressure thereto, the valve having a first outlet conductor 152 leadingto the chamber 127 of the diaphragm housing 125, and a second conductor153 leading to the chamber 12S of the diaphragm housing 125. The valve150 is, of course, adapted to place the conductor 151 alternately incommunication with the conductors 152 and 153. The

operation of this modification of the invention is subo stantially thesame as that previously described with the exception that the pilotvalve 136 functions, in addition to switching the valve 137 aspreviously described, also to switch the valve 150 yand alternatelypressurize the chambers 127 and 12S while venting the opposite charnberthrough one of the vents 154 of the `four-way valve 150.

The modification of FIG. 6 includes a left hand cylinder 155 and a righthand cylinder 155 having their outer ends closed by heads 156 and 156.Inner heads 157 and 157' close the inner ends of the cylinders 155 and155', respectively, -and are joined by a tubular connection member 158.The heads 157 and 157 are provided with axial bores 159 and 159 carryingpacking glands 16) and 160' through which a double ended pis- 'ton rod161 is reciprocable. A piston 162 is secured to the yleft hand end ofthe rod 161 and is freely slidable in the cylinder 155, a similar piston162' being carried by the right hand end of the rod 151 and being freelyslidable within the cylinder 155. Within the tubular connection member158, a pair of spaced actuating rings 163 and 163 are mounted upon therod 161 to the left and right hand sides respectively, of the operatingarm or pin 164 of a pilot valve 165 similar in all respects to the pilotvalves 61 and 61.

The inner heads 157 and 157 are provided with inlet ports and inletconductors 166 and 166 having therein check valves 167 and 167', theinner heads also having outlet ports and conductors 168 and 16S' alsocarrying check valves 169 and 169. Thus, by reason of the pres- 12 enceof the several check valves, as the pistons y162 `and 162 arereciprocated within the cylinders 155 and 155', tiuid will be pumpedfrom the conductors 166 and 166 through the spaces between the pistonsand the inner heads and `outwardly through the outlet conductors 168 and168.

For reciprocating the piston rod 161 and the pistons 162 and 162', thepilot valve 165 is provided with a pilot fluid inlet supply conductor17h, -a venting conductor 171, and a controlled iluid conductor 172leading t-o the underside of a diaphragm 173 enclosed in a diaphragmrousing 174 and adapted to operate a four-way valve 175. rlhe valve 175carries ian inlet supply conductor 176 `for motive uid admitted underpressure, an outlet conductor 177, and a pair `of controlled fluidconductors 178 and 173. The conductor 175 is connected through a needlevalve or other suitable type of control valve 179 to the head 156 and tothe interior of the cylinder 155 outwardly of the piston 162, while theconductor 17S is connected through a control valve 179', similar to thevalve 179, to the head 156 and to the interior of the cylinder outwardlyof the piston 162.

Here again, the areas of the pistons 162 and 162 exposed to theconductors 178 and 17 3 are greater than the areas exposed to theconductors 166 and 166 as well as the conductors 16S and 165 by reasonof the presence of the piston rod 161. Accordingly, although fluid underpressure may be admitted to the outer faces of the pistons from a sourceof tiuid under a given pressure, and another iiuid pumped through theconductors 168 and 16S into the same source, the differences in area ofthe two sides of each of the pistons as well as the differences in thevolumes of uid being pumped, will permit the unit to operate. Assumingthat the pumping structure is being employed in a glycol typedehydration unit for natural gas `and that both the concentrated anddilute glycol solutions are being pumped, in the position of thestructure illustrated in FIG. 6, dilute glycol solution will be flowing`from the conductor 176 through the valve 175 to the conductor 178 andto the outer `face of the piston 162 to drive that piston, the rod 161,and the piston 162 to the right. This action will pump concentratedglycol solution from the right-hand portion of the cylinder 155 throughthe outlet conductor 16S to the dehydration tower, will draw a freshquantity of concentrated glycol solution into the left-hand portion ofthe cylinder 155' from the inlet conductor 166', and will pump diluteglycol solution from the right-hand portion of the cylinder 155' throughthe conductor 173 and the valve 175 to the outlet conductor 177 leadingto the glycol regeneration or reconcentration unit. As the rod andpiston assembly approaches the right-hand end of its stroke, theleft-hand actuating ring 163 will engage the arm 164 to switch the pilotvalve 165, closing the vent 171 and admitting pilot gas under pressurefrom the conductor 1741 through the conductor 172 onto the underside ofthe diaphragm 173 thus switching the four-way valve to vent theconductor 178 and pressurize the conductor 178. Of course, upon reachingthe left-hand end of the stroke of the piston and rod assembly, the arm164 will be switched to the left, again reversing the operation andpressurizing the conductor 178 while venting the conductor 178. Asmentioned in connection with the ydiscussion of the modication of FlG.4, some quantities of gas or other iiuid will also be admitted throughthe valve 175 to the conductors 178 and 176 and will ultimately beexhausted through the outlet conductor 177. The concentrated glycolsolution inlet conductors 166 and 166 are shown as manifolded into acommon inlet conductor 130, but it is apparent that the inlet conductorsmay remain isolated so as to pump two different uids through the twocylinders of the assembly. Of course, the outer conductors 168 and 168'may also be m-anifolded in a similar fashion, and this would bepreferable in most instances when the pumping unit is being employed inconjunction with a gas dehydration unit. In FIG. 7, there is shown asingle acting modification of the form of the invention illustrated inFIG. 6, this structure being identical in many respects to that shown inFIG. 6 and the same numerals being applied thereto, the only importantdifferences in the structure being the elimination of the cylinder 155'and the replacement of the inner head 157 with an end head 181 carryingan adjusting screw 182 and a spring follower 183 supported upon theadjusting screw and confining a compression spring 184 between thefollower 183 and the end of the piston rod 161. The four-way valve 175is also replaced with a three-way valve 175 since the control of fluidto and from only the single cylinder 155 is required. This furthermodification operates in substantially the same manner as themodification of FIG. 6, the pilot valve 165 being actuated to admitalternately dilute glycol solution or other fluid under pressure to theleft hand end of the cylinder 155 through the inlet conductor 176 andthereafter exhausting said fluid through the outlet conductor 177 so asto pump concentrated glycol solution or other fluid through the righthand portion of the cylinder 155. The spring 184, of course, functionsto return the piston 162 to its left hand position during the venting ofthe dilute glycol solution or other uid.

Thus, a new combination has been disclosed, a combination employing oneor more driving pistons and one or more driven pistons powered by thedriving pistons with snap-action, toggle-type, pilot valves operatedpositively and reliably from the driving piston through either a director indirect but positive mechanical connection for the purpose ofswitching a suitable control valve which regulates the flow ofmotivating fluid under pressure to the piston for driving the pumpingunit and reciprocating the piston for pumping operations. Allpossibility of the device failing to switch or reverse strokes due toextremely slow rates of operation are eliminated, and at the same time,positiveness and certainty of operation is assured regardless of therapidity with which fluid is being pumped. The net result is a positivedisplacement pump adapted for the supplying of controlled quantities offluid at controlled rates and at high pressures utilizing motivatinguids under relatively low pressures but assuring complete positivenessof operation and eliminating the possibility of pumping failure short ofthe physical failure of some component portion of the structure. Even atpumping rates at which movement of the several pistons may not beVisually observed, a point will be reached in the stroke of the pumppiston at which one of the snap-action valves, by reason of itstoggle-type construction, will shift almost instantaneously from oneposition to another to provide positive and certain reversal of the pumpstroke.

In FIG. 8 of the drawings there is illustrated a snapaction, toggle-typevalve or pilot valve typical of the valves 61 and 61', 94, 130, and 165,hereinbefore mentioned, the valve of FIG. 8 being identified as valve 61for purposes of identification. This valve is constructed in accordancewith U.S. Letters Patent No. 2,860,660, and includes a rectangular valvebody 185 having a longitudinal bore or passage 186 with its right-handend screwthreaded at 187 to receive a bushing 188 and control conductor189. An upper screwthreaded passage 190 opens upwardly from the upperside of the bore 186 into a screwthreaded counterbore 191 and receives abushing 192 having a valve face 193 on its lower end. The counterbore191 receives a bushing 194 and a vent conductor 195. A secondscrewthreaded and lower passage 196 opens downwardly from the lower sideof the bore 186 into a screwthreaded counterbore 197 which receives abushing 198 and pilot fluid supply conductor 199. A bushing 200 ispositioned in the passage 196 and has a valve face 201 on its upper end.An operating lever 202 is pivotally mounted intermediate its ends upon apivot pin 203 spaced inwardly from the left-hand end of the passage 186,an annular packingl 204 enclosing the medial portion of the pin 202 insnug surrounding and sealing relationship substantially in the plane ofits pivotal mounting, and a hollow plug 205 being screwthreadedlyreceived in the left-hand end of the passage 136 for maintaining thesealing member 204 in position. The inner end of the pin 202 is notchedas shown at 206 to receive one end of a yoke or fork 207 having itsopposite end engaging a spool-shaped, double ended valve core 208positioned lfor reciprocal movement between the valve faces 193 and 201.A toggle spring 209 encompasses the yoke 207 and has one end connectedto the inner end of the larm 202 while its opposite end is connected tothe medial portion of the yoke 207 in order to provide a toggle or snapaction when the pin 201 is swung in an arc about the pivot pin 203.Obviously, in the operation of the valve and starting in the positionthereof shown in FIG. 8, las the outer and projecting end of the lever202 is moved downwardly, the yoke 207, by reason of the presence of thespring 209, will continue to urge the valve core 208 upwardly againstthe valve seat 193 until such time that the pin 202 and yoke 207 havereached and passed a relative dead center position, at which time, thespring 209 will function through a toggle action to snap the yoke 207quickly downwardly and thus valmost instantaneously move the valve corefrom engagement with the seat 193 into engagement with the seat 201. Thereverse action, of course, occurs upon the return upward movement of thepin 202. In this manner, the valve functions to shift the conductor 189quickly from communication with the conductor 199 into communicationwith the conductor 195 and through a reverse action upon reversemovement of the pin 202.

The foregoing description of the invention is explanatory thereof andvarious changes in the size, shape and materials, as well as in thedetails of the illustrated construction may be made, within the scope ofthe appended claims, without departing from the spirit of the invention.

What I claim and desire to secure by Letters Patent is:

l. The combination with a fluid-operated pump including a cylinder, adriving piston in the cylinder, means for admitting a motive fluid underpressure to the cylinder for moving the driving piston therein,fluid-actuated valve means for controlling the admission of the motivetiuid to the cylinder, and fluid pumping means connected to and drivenby the driving piston, of a snap-action valve for controlling theadmission of actuating tiuid to the duid-actuated valve means, andactuating means for the snap-action valve including an actuating rodoperated by the piston, and spaced actuating elements carried by the rodfor actuating the snap-action valve.

2. The combination with a uid operated pump including a cylinder, adriving piston in the cylinder, means for admitting a motive fluid underpressure to the cylinder for moving the driving piston therein,fluid-actuated valve means for controlling the admission of the motivefluid to the cylinder, and fluid pumping means connected to and drivenby the driving piston, of a snap-action instantaneously opening andclosing valve for controlling the admission of actuating fluid to thefluid-actuated valve means, and actuating means for the snap-actionvalve including an actuating rod extending into the cylinder forengagement by the piston, and spaced actuating rings carried by the rodfor actuating the snap-action valve.

3. The combination as set forth in claim 2 wherein the snap-action valveis provided with an actuating arm projecting between the actuating ringsof the actuating rod, said rings being spaced apart a distance greaterthan the path of movement of the actuating arm.

4. The combination as set forth in claim 2 wherein the fluid-actuatedvalve means is a springless four-way valve.

5. The combination with a fluid-operated pump including a cylinder, apiston and rod assembly for pumping a uid, at least the piston of saidassembly being spr/dona 15 disposed in the cylinder, means for admittinga motiv fluid under pressure to the cylinder for moving the pistontherein, and fluid-actuated valve means for controlling the admission ofthe motive fluid to the cylinder, of a snapaction instantaneouslyopening and closing Valve for controlling the admission of actuatingiluid to the fluidactuated valve means, an actuating rod operated by thepiston and rod assembly, spaced actuating elements carried by theactuating rod, and means having connection with the snap-action valvefor alternate engagement with the actuating elements to instantaneouslyopen and close said snap-action valve.

6. The combination set forth in claim 5 wherein the means havingconnection with the snap-action valve includes an arm positioned fordirect engagement with and movement by the spaced actuating elements.

7. The combination set forth in claim 6 wherein the actuating elementsare disposed on each side of the arm and are spaced apart a distancegreater than the movement of said arm.

8. The combination set forth in claim 5 wherein the actuating rod haslost-motion connection with the piston and rod assembly.

9. The combination set forth in claim 5, including means for admittingand discharging a pumped fluid to and from the cylinder on the side ofthe piston opposite the side to which the motive lluid is admitted, andmeans connected to said piston for driving said piston in Clt adirection opposite that in which it is moved by the motive uid forpumping said motive uid from said cylinder.

10. The combination set forth in claim 5 wherein the piston and rodassembly includes a pair of cylinders with a piston in each cylinder,the motive fluid being admitted to one side of each piston for movingthe pistons in unison.

ll. The combination set forth in claim 5, spring means urging the pistonand rod assembly in a direction opposite to that in which said assemblyis moved by the motive fluid, and means for admitting a second tluid tothe cylinder on the side of the piston opposite the side `to which saidmotive uid is admitted and for discharging the second Huid.

References Cited in the file of this patent UNITED STATES PATENTS691,343 Abendroth Jan. 21, 1902 1,674,614 Berkman June 19, 19281,766,010 Binderup June 24, 1930 1,825,411 Murphy Sept. 29, 19312,235,544 Wold Mar. 18, 1941 2,287,779 Carlisle June 30, 1942 2,296,647McCormick Sept. 22, 1942 '2,658,485 Dreyer Nov. 10, 1953 2,792,785Hayden May 21, 1957 2,900,917 Schinnerer Aug. 25, 1959

